Such failures can be costly, and so retailers and others who place bets on these items are interested in reliable signals as to whether or not a product will succeed. Now some business-school marketing gurus have identified a strange breed of consumers who function as human pointers signaling a flop ahead.

The researchers, at Northwestern University and the Massachusetts Institute of Technology, call this group of consumers “harbingers of failure” for their habit of buying products destined to fail. These grim reapers with credit cards are reliable contra-indicators: Their taste for, say, Frito-Lay Lemonade is a strong sign of doom that can help retailers cut their losses early.

The scientists describe their work in a new paper focused on one big chain of convenience stores in the Midwest and Southwest. They analyzed more than 10 million transactions by 127,925 customers who used the chain’s frequent-shopper card, and they defined a flop as a product no longer stocked after three years. (In a sample of 8,809 new products, 40% survived that long.) Customers who bought at least two new products were assigned “flop affinity” scores, depending on the proportion of their new-product purchases that flopped.

The results? If a new product was bought heavily by customers with a flop rate exceeding 50%, that was a good sign that the item would be a bust. For instance, if this group accounts for half of a new product’s sales instead of a quarter, the likelihood of the product succeeding falls by 31%.

Lead scientist Eric Anderson says that the overall findings appear to be robust. They hold up, for instance, when product success is defined as lasting just two years. And the scientists have since replicated their findings at stores all across the country.

Who are these harbingers of failure? Researchers call them “preference minorities”—a label that fit 13% of the consumers in this study. As compared with most other shoppers, they tend to have more education, higher income and more children. Their favorite store is Costco, and Dollar General is the last place they would shop.

They presumably skew female, because women do most of the shopping. And they seem to like trying new things, perhaps because they can bear the cost of failures, or because their larger families will gobble down anything once. They also buy more niche products than the average consumer.

Given their income, education and readiness to experiment, one might think that these consumers would be supermarket trendsetters. So why don’t their choices catch on? Do they all wear Birkenstocks and listen to choral music while driving around in Saabs?

Not likely, says Dr. Anderson, who acknowledges that more research is needed to pinpoint their characteristics. But it may be that they just don’t proselytize on behalf of their new discoveries—or that their tastes are just too quirky.